Microbial competition and cooperation in the phyllosphere

Suitable for Master students for at least six months.

The phyllosphere (the aerial parts of plants), harbors a rich microbial life, including bacteria, fungi, viruses, and yeasts. The phyllosphere is a harsh and dynamic environment where yeasts are exposed to several different (a)biotic stresses, including low nutrient availability, ultraviolet (UV) radiation, and temperature and humidity oscillations, as well as toxic compounds (mycotoxins and fungicides).

Yeasts have diverse adaptive traits to cope with these conditions, such as biofilm formation, carbon and nitrogen acquisition, and the production of pigments and killer toxins (Figure 1). To date, understanding of the adaptive and competitive mechanisms used by yeasts to colonize the phyllosphere remain largely unknown. In this project, we will use our recently stablished ‘Phyllosphere Yeast Repository’ - an extensive collection of yeast isolates and genomes - to assess competition and cooperation in the phyllosphere. Interactions will be investigated under limited nutrient conditions to test if and how resource limitation promotes cooperation (e.g. metabolic cross-feeding) or competition (e.g. production of killer toxins, VOCs).

• Aims
   
  • 1. To investigate how yeasts compete and cooperate with other yeasts and bacteria in the phyllosphere
  • 2. To determine the production of killer toxins by phyllosphere yeasts
• Approaches & techniques: culturing techniques, designing synthetic communities, in vitro competition assays, evolutionary experiments, growth rate determination, qPCR
• Location & contact: Department of Microbial Ecology, Netherlands Institute of Ecology, Wageningen, The Netherlands

For further information and application:  v.cordovez@nioo.knaw.nl (Viviane Cordovez)

Relevant literature

Gouka, L.; Vogels, C.; Hansen, L.H.; Raaijmakers, J.M.; Cordovez, V. (2022). Genetic, phenotypic and metabolic diversity of yeasts from wheat flag leaves. Frontiers in Plant Science 13:908628.

Gouka, L.; Raaijmakers, J.M.; Cordovez, V. (2022). Ecology and functional potential of phyllosphere yeasts. Trends Plant Science S1360-1385(22)00159-5.

Boynton, P.J. (2019) The ecology of killer yeasts: Interference competition in natural habitats. Yeast 36: 473– 485.